The present invention relates to automatic bundling machines, and in particular to such bundling machines for wrapping rolled tissue products in compressed stacked rows with thermoweldable material.
Devices and systems for wrapping articles in thermoplastic and/or thermoweldable stretchable film material are known in the art. Such an apparatus is generally disclosed, for example, U.S. Pat. No. 4,144,697 wherein articles to be wrapped are moved through a tunnel of stretchable film material which enclosing the articles in a tube of film which is subsequently cut before and after the enclosed article and folded and sealed. Another approach for rolled products such as toilet tissue, paper towels and other paper products inserts a selected number of the products into a preformed plastic bag, which is subsequently sealed at its opened end after the articles are inserted therein. A similar device for individually wrapping the rolls in plastic material is described in U.S. Pat. No. 4,018,031 which also makes use of preformed bags. Another approach for wrapping such articles in groups has been to convey the articles through a wrapping machine which surround the groups of articles with a sheet or web of wrapping material and subsequently seals the material around the articles. Such devices are described, for example, U.S. Pat. Nos. 3,660,961; 3,794,154; and 3,807,128.
In handling wound rolls of larger sizes, such as rolls of paper towels, it is a problem in the art to convey such rolls for bundling in a rapid manenr which does not cause clogging or misalignment of the rolls. This problem is partilarly acute when the rolls must be upended, that is placed so that the inner cardboard tube or roll is vertical, during the bundling procedure. Because of the weight of such larger rolls, the base of the rolls resting on the surface along which the rolls are to be conveyed causes excessive friction with the base, thereby resisting easy movement of the rolls in this position. Various devices such as that disclosed in U.S. Pat. No. 4,033,862 have been heretofore utilized to avoid conveying the rolls in this position by pushing the rolls, resorting to complicated gripper mechanisms for grabbing the rolls individually.